Photo: Why RO Membrane Maintenance is Important

[SV THIRD DAY]

It's one thing to be told to take good care of your RO Membranes, but sometimes it helps to see what one looks like that hasn't been taken good care of.

This is what a good membrane looks like:



Now here is what a RO Membrane looks like covered in biological growth and slime. You can see the spiral layers of membrane material inside the round ports is all black. This membrane only had 50hrs on it and was a year old.



So the moral of the story, don't let this happen to you. Take care of your membranes and don't let the water maker sit for too long of periods without running, fresh water flushing or pickling.

[Lepke]

Even in fresh water stuff will grow, but seems to be salvageable.

[BlackAdder]

Rich, quick question for you. I have an Aqua-Base XD-122 watermaker which has been sitting unused for 1.5 years at least and probably a good deal longer as I believe the PO said she never used it as well. I would like to start using the damn thing.

My plan was to decouple the motor from the CAT pump and try the various components individually first. Booster pump, etc. I have a TDS meter. I believe I read once on CF that someone said to just fire it up and flush it. Then give it a run for a while and measure TDS and maybe all will be good. But now that you showed that pic, I'm thinking that could be the state of my membrane even if it's been properly pickled (which I'm thinking it has been). What do you think? Any advice?

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[SV THIRD DAY]

I think the general advice of fire it up and run it, still makes sense.
First just make sure your boost pump is supplying enough flow rate to your CAT Pump, if it is, then let it run at 150-200psi for a few minutes before bringing it up to 800psi, where I would let it run for another few minutes before starting to take TDS readings. If the unit has sat for that long, I would put in some new prefilters and a new Activated Carbon filter for the fresh water flush. A new RO Membrane TDS will be around 150ppm-ish and anything over 500ppm and it's time to replace. So somewhere in that range would be "normal". Let me know what you find and I'll be happy to help. If any questions pop up during the start-up, just give me a call at 619-609-3432 and I will be happy to help.

Good luck.

[BlackAdder]

Rich, you are too kind. Really. My next watermaker or Cool Blue I will buy from you on principle alone!

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[phorvati]

Originally Posted by SV THIRD DAY

I think the general advice of fire it up and run it, still makes sense.
First just make sure your boost pump is supplying enough flow rate to your CAT Pump, if it is, then let it run at 150-200psi for a few minutes before bringing it up to 800psi, where I would let it run for another few minutes before starting to take TDS readings. If the unit has sat for that long, I would put in some new prefilters and a new Activated Carbon filter for the fresh water flush. A new RO Membrane TDS will be around 150ppm-ish and anything over 500ppm and it's time to replace. So somewhere in that range would be "normal". Let me know what you find and I'll be happy to help. If any questions pop up during the start-up, just give me a call at 619-609-3432 and I will be happy to help.

Good luck.

Very useful info. Thanks. Just wanna add that water temperature, salinity, and pressure, influence ppm numbers as well. When I run it for the first time in the spring up in New England (40F water), I am at 150-200ppms, but by late august numbers are in the 400s.